One of the reasons Americans are still buying huge vehicles is that they occasionally need to haul large loads across town or on a road trip, and small cars just don’t do the job. Rinspeed[1] has come up with a creative solution to turn even the tiniest electric city car[2] into a road-tripping hauler. The Dock + Go Mobility Concept is essentially a small pickup bed with an optional glass cover that fits onto the back of any electric city car, such as the Smart[3] car pictured here. But it’s even better, and greener, than that.

The Dock + Go concept offers extra battery capacity to offset its extra weight on the back of your car, and the rear wheels charge the battery pack. So now you can add space and range to your little electric runaround at the same time. We love the modular[4] concept, since you can leave the extra space at home until you need it, which will give you better range than shape-shifting city cars that carry their extra space around with them. Frank M. Rinderknecht, founder and CEO of Rinspeed, is calling this new concept a Vario-Hybrid.